>>I use pkzip25 programmatically all the time, but for manual zipping/unzipping I use whatever TotalCommander uses, which I thought was pkzip25, but obviously isn't. In it, ctrl+pgdn opens the currently selected file as an archive (and it will detect the type of the archive - works with almost anything except 7z and arj).
>
>and for RAR you have to point Totalcommander to WinRAR, which it then can drive programmatically...
>which you can do also via commandline, giving you multithreaded compression gaining a nice percentage in speed and smaller results

Which I probably did, or something came with some update (how many years ago, who knows). I know it now just works, so .rar is not in the parenthesized list above.